Recent Results on B Meson Oscillations

Abstract

This paper presents recent time-dependent measurements of neutral B meson oscillations. Similar to the $K^0$--${\bar{K}}^0$ system, there are two such systems involving the b quark: $B_d^0$--${\bar{B}}_d^0$ and $B_s^0$--${\bar{B}}_s^0$. Thus the physical states are respectively $K_S$ and $K_L$, $(B_d{)}_S$ and $(B_d{)}_L$, and $(B_s{)}_S$ and $(B_s{)}_L$. The oscillation between each pair of states can be used to determine their mass difference. The present world average for the $(B_d{)}_S$--$(B_d{)}_L$ mass difference is $\Delta m_d=0.457\pm 0.019p{s}^{-1}$ (or $(3.01\pm 0.13)\times 10^{-4}$ eV). Using $f_{B_s}$ = 12\% (the fraction of $B_s$ produced in b events), the current lower limit on the corresponding $\Delta m_s$ is 6.1 ps${}^{-1}$ (or $4.0\times 10^{-3}$ eV).

Invited talk at the XVII International Symposium on Lepton-Photon Interactions, Beijing, China, 1995. 26 pages, latex, 15 figures